P1158: REAL-WORLD TREATMENT PATTERNS AND ECONOMIC BURDEN OF PATIENTS WITH MARGINAL ZONE LYMPHOMA
Authors: K. Yang, T. Liu, B. Tang, B. Shah
Journal: HemaSphere (2022)

Background: Marginal zone lymphoma (MZL) is an indolent non-Hodgkin lymphoma that is treatable, yet incurable with a remitting and relapsing disease course. Given its disease rarity and underlying heterogeneity, MZL remains understudied with limited real-world evidence on how current treatment pattern conform to clinical guidelines, and the economic outcomes associated with current treatments. Aims: This study aimed to assess real-world treatment patterns, costs, and healthcare resource utilization (HRU) in US MZL patients. Methods: A retrospective, observational study was conducted using the IBM MarketScan® commercial and Medicare supplemental claims dataset (2017-2020). Newly diagnosed adult MZL patients (≥18 years) continuously enrolled 6 month pre- and 3-month post-index date, defined as the first diagnosis date, were included. Treatment regimens were identified by line of therapy and mutually exclusively categorized as rituximab monotherapy (R-mono), bendamustine + rituximab (BR), rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), ibrutinib, or other. Descriptive analyses were conducted to assess patient sociodemographic and clinical characteristics, and treatment utilization patterns including the frequency, duration, and discontinuation of each treatment regimen. Costs and HRU assessed included inpatient, outpatient, and pharmacy visits per-patient-per-month (PPPM). Treatment regimens, costs, and hospitalizations were examined overall, and by line of therapy. Multivariable logistic regression was conducted to examine predictors of costs and HRU. Results: Among the 2491 newly-diagnosed MZL patients (median age = 63 years; 52% male), 59% were commercially insured (median age = 57 years) and 41% in Medicare (median age = 76 years). The most common comorbidities were hypertension (44%), diabetes (17%), atrial fibrillation (AF; 16%), and gastroesophageal reflux disease (15%). Mean time from diagnosis to treatment initiation was 223 days. A total of 1,781 (72%) patients received first-line (1L), 518 (29%) patients received second-line (2L) and 239 (13%) patients received third-line (3L) therapies. R-mono was the most common regimen across both commercial and Medicare patients and all treatment lines (Table). R-CHOP and BR were the second most used regimen in 1L with decreased use in 2L+. Ibrutinib was used more in 2L+ setting but had the lowest 1L PPPM cost (median $2958.9) than other regimens. Overall MZL patients had PPPM 4.6 outpatient visits, 0.5 hospitalization, and mean length of stay of 2.6 days. Total PPPM healthcare cost was $19,895.8. Multivariable regression showed that baseline comorbidities (AF, renal disease, neutropenia) and treatment discontinuation were significant predictors of higher costs and HRU. Image:Summary/Conclusion: This real-world data suggested that the overall US MZL real-world treatment pattern across lines of therapy follows the regimen recommendations by the National Comprehensive Cancer Network clinical practice guidelines and that MZL patients incur high economic burden. Future studies are needed to evaluate long-term outcomes and the impact of heterogenous MZL subtypes.